Author: Richard Sternberg
The “Why” of the Fly “Y”: Reflections on “Junk” DNA
Let us give some thought to the Y chromosome of Drosophila melanogaster, that engaging fly which is the bond-servant of genetics.
Limited-Time Offer! Act Now! Operators Standing By! MagiMold�!
MagiMold� works because of prions, special proteins that allow a cell to evolve before its DNA does.
Let’s Do the Math Again
Earlier today I criticized Calvin College biologist Steve Matheson’s incorrect view of “junk” DNA. Matheson had argued in February that the human genome contains about 190,000 introns (stretches of non-protein-coding DNA that interrupt protein-coding genes), of which “only a handful” had important functional roles. “How many? Oh, probably a dozen,” he wrote, “but let’s be really generous. Let’s say that a hundred introns in the human genome are known to have ‘important functional roles.’ Oh fine, let’s make it a thousand.” On the contrary, I pointed out that at least 90% of genes are alternatively spliced, meaning that 0.9 x 190,000 = 171,000 introns are involved in alternative splicing, an essential process that helps to ensure that the proper proteins Read More ›
Matheson’s Intron Fairy Tale
The failure to recognize the importance of introns “may well go down as one of the biggest mistakes in the history of molecular biology.” –John Mattick, Molecular biologist, University of Queensland, quoted in Scientific American On Friday, May 14, I watched as Steve Meyer faced his critics–two of them anyway, Art Hunt and Steve Matheson–at Biola University in Los Angeles. Matheson had previously claimed that Meyer misrepresented introns in his book, Signature in the Cell. (Introns are non-protein-coding sequences of DNA that occur within protein-coding regions.) In a blog post dated February 14, Matheson had accused Meyer of “some combination of ignorance, sloth, and duplicity” for stating in his book that although introns do not encode proteins they nevertheless “play Read More ›
Beginning to Decipher the SINE Signal
Remember the analogy of the two moons I used yesterday to discuss the distribution of SINEs in the mouse and rat genomes? Well, I am going to use it again today, but only for a moment. Moon Mysteries and the Lunarlogos Foundation Suppose you are keenly interested in the topography of one of the moons, named Y6-9. Suppose also that the books you first select to read on the topic are popular works, written by “experts” who are “living legends.” As you read through the works, you find paragraphs here and there about how utterly decrepit Y6-9 is, and how this space body exemplifies eons of random events. The authors argue that we already knew all there was to know Read More ›